What is "dictionarius"

Dictionarius is a short work written about the year 1200 by the medieval English grammarian Johannes de Garlandia or John of Garland. For the use of his students at the University of Paris, he lists the trades and tradesmen that they saw around them every day in the streets of Paris, France. The work is written in Latin with interlinear glosses in Old French.

Johannes de Garlandia is thought to have invented the term dictionarius, the source of the English word dictionary and of similar words in many other modern languages.